管涔山青扦(Picea　wilsoni)天然林年龄结构及其动态的研究

AGE STRUCTURE AND DYNAMICS OF NATURAL SPRUCE (PICEA WILSONII) FORESTS IN GUANCEN MOUNTAINS

对种群年龄结构的研究表明，虽经人为频繁干扰，管涔山青扦天然林仍表现出异龄林结构特征，立木年龄范围超过一个龄级期，根据年龄结构特征值可分为相对同龄林、相对异龄林和异龄林３种类型。林下新一代种群的数量和结构受林冠郁闭度和结构的影响。具垂直郁闭型林冠的异龄林，林下更新数量充足，幼苗幼树年龄结构合理；而水平郁闭型林冠，不利于新一代种群的发生和发展。青扦种群年龄结构受种群发生和自疏两个过程的控制，林下种群的发生以小规模林冠空隙干扰下的连续更新为主。青扦华北落叶松混交林。

Age structure of natural spruce forests in Guancen Mountains remained the characters of uneven aged stands after long time of human disturbance. Age ranges of trees within the stand were all over one single age class(20 years). According to characteristics of age structure, the forests were divided into three types, that is, relative even aged forest, relative uneven aged forest, and uneven aged forest. The regenerations under forest canopy were greatly affected by density and structure of canopy. The forests with uneven aged vertical canopy had enough seedlings and sound age distribution. However, under a horizontally crowded canopy, the regeneration was not good enough to develop a sound age structure. It also showes that the dynamics of age structure was controled by regeneration, natural thinning, and disturbance. It was proved that the regeneration of the population depended on a disturbance regime of forest canopy, especially of development of seedlings into saplings. It was also proved that the mixture of Spruce and Larix principis rupprechtii was a dynamic stable community in their co suitable region.